Water Notes:

Water:

Composed of two hydrogen atoms and one oxygen atoms

H2OPolar Molecule

Polarity:

Unevenly distributed charges due to unequal forces placed on bonding electrons

Oxygen ends slightly negativeHydrogen end slightly positive

Results of Polarity:

Allows water to form Hydrogen Bonds

Result of Polarity:

Hydrophilic: All polar molecules attracted to water

Result of Polarity:

Hydrophobic: Repels non-polar substances such as water

Stabilizes Temperature:

Hydrogen bonds between molecules absorb heat energy, thus molecules do not move faster, therefore temperature does not rise as quickly

Need more heat energy to change temperature

Cohesiveness:

Hydrogen bonding locks molecules together

Surface Tension: Cohesion at the water’s surface

Cohesiveness:

Adhesion: when water attaches to non-water molecules

ADHESION

COHESION

Cohesiveness:

Capillary Action: Movement of water up

Universal Solvent:

Ions and polar molecules readily dissolve in water

Substances such as salt are pulled apart by attraction of opposite charges due to polar structures

Density:

Water has a density of 1g/mLOne of the few substances that is less

dense as a solid than liquidDue to hydrogen bonding and resultant

pockets

Water Cycle

The constant cycling of water within atmosphere and lithosphere

Condensation

Water vapor condenses into liquid water

Precipitation

Liquid/solid water falls to the Earth

Evaporation

Liquid water heats up, changes to water vapor and enters the atmosphere

Transpiration

The evaporation of water from plants

Runoff

Water not absorbed into the soil runs down the landscape by gravity